JPS6163204A - Lift arm operation structure of agricultural tractor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a first getter/shichometer for detecting the height, and a first getter/shichometer for connecting a work device so as to be able to rise and fall, and for mounting a toe arm to an aircraft body. A chopstick 2 potentiometer is provided to detect the amount of operation of the operating tool with respect to the 7 arm, and the l1i7
An ft1lJ control mechanism is provided for automatically operating a hydraulic actuator for driving the toe arm based on information from both potentiometers so that the toe arm is driven by a stroke proportional to the operation amount of the sweeping tool, Connected work 1
The present invention relates to a lift arm operation structure for an agricultural tractor configured to raise and lower a device by position control.

[Conventional technology]

Conventionally, in the above agricultural tractor, if the first potentiometer malfunctions, or the position shifts due to improper adjustment of the fixing position, loosening of the fixing screw, etc.,
Even if the lift arm is raised by the control mechanism until the stopper for the toe arm or the 97 toe arm drive piston acts, or even if the lift arm does not hit the stopper, the high level Vr- exceeding the set limit that should be operated by the control mechanism. It was structured so that it could be raised up to

[Problem that the invention seeks to solve]

As described above, when the lift arm is raised until the stopper acts, the pressure oil supplied from the pump to the actuator for driving the lift arm returns to the tank through the relief valve. Problems may occur in which the temperature rises abnormally.Also, if the temperature rises to a level higher than the set limit, the temperature may rise.For example, if the piston for driving the lift arm and the piston rond are in contact type, the connection work may be difficult. The device bounced up due to running vibrations and the lift arm collided with the stopper, resulting in the IJ7) arm and stopper being deformed or damaged.

The purpose of the present invention is to prevent the IJ-7 from being raised or the 7th arm to be pressurized, and the 7th arm from being raised due to the jumping up of the connecting work device, even if a malfunction or positional shift occurs at the end of the first button. The objective is to ensure that the stopper is stopped at a position where no collision occurs.

[Means for solving problems]

The present invention is characterized in that in the aforementioned lift arm operation structure for an agricultural tractor, the forelift lift arm is raised to a set stop position higher than the set lifting limit to be operated by the control mechanism; A sensor is provided to detect a second situation in which the lift arm is raised to a high level beyond the set stop position, and if the sensor is present in the detection state of the first situation, it takes priority over the control mechanism. When the hydraulic actuator is automatically stopped and the sensor is present in the detection state 6 of the 21st gear, the hydraulic actuator is automatically operated to the lowering side of the toe arm in priority to the control mechanism. The purpose is to provide a mechanism to
It is 9.

[Effect]

1Et (Set the above-mentioned stop position at a position where there is still enough movement margin on the upward side to prevent the Ff actuator from hitting the stopper or the toe arm hitting the stopper even if the connecting work device jumps up. Then, Even if the first detensiometer malfunctions or is misaligned and the lift arm is lifted beyond the set lifting limit, when the lit arm reaches the set stop position, the control mechanism operates to stop the lift arm at this position.

For example, the 7-arm lift rate can be adjusted quickly,
Even if the lift arm rises too high above the set stop position due to inertia despite the stop operation of the control mechanism, the control mechanism returns the lift arm to the set stop position.

〔Effect of the invention〕

Therefore, even if the first potentiometer malfunctions or is misaligned, and even if the lift arm is set to raise at a high speed, it will not be possible to prevent the actuator from coming into contact with the stopper. The lift arm is stopped by operating the control valve to the neutral position, and the lift arm is stopped at the set stop position to prevent abnormal temperature rise due to IJ-7 of the hydraulic fluid. This makes it possible to use the oil for a long period of time, and also prevents collision damage caused by the lifting arm and stopper of the working device, making it possible to use the device for a long period of time.

〔Example〕

As shown in Figure 5, a pair of left and right front cars, Kusunoki (1), (1
) and a rear wheel +21 e +21 that can be driven at h2, a rotary tilling device (4) is connected to the rear of the agricultural tractor via a link mechanism (3) that can be moved up and down by VC drive so that it can be raised and lowered. At the same time, the riding type tiller is constructed by transmitting power from the tractor to the tiller (4) through the rotary shaft (6).

The link structure (3) consists of a pair of left and right glued arms (6) that can be vertically moved to the mission case (8), which forms the rear part of the fuselage, via a rotating shaft ( ). At the same time, attach a pair of glue 7 to arm f6)
, fil, and a pair of left and right lower links +9) extending from the mission case (8) so as to be able to swing vertically.
91 are connected to each other separately by a pair of lifts, and are operated up and down using the operation structure described in detail below.

That is, as shown in FIG.
1 arm [1] is configured to be oscillated by a single VJ type hydraulic cylinder, which is an example of a hydraulic actuator, installed in a mission case (8), and as shown in FIG. 8, the mission case (8) Stay α
1J by the first potentiometer I installed through J
7. When attaching the toe arm (6) to the mission case (8), the rotary operation shaft (of the potentiometer (141)
14a) is coaxially interlocked with the rotation support shaft (7). As shown in FIG. 1, a second potentiometer is connected to the dial port so as to detect the direction and amount of operation of this potentiometer! 16). And, the first potentiometer I is controlled to control the shilling qz through the control mechanism [17].
The electromagnetic control pulp σ& is linked to the circuit (19u) for operating the control pulp book to the upward side of the seventh arm (6) and the circuit (19d) for operating the control pulp book to the downward side of the seventh arm (6). Then, the control mechanism ar+ is connected to both potentiometers 041 and (1
6) Compare the input values from each, and if there is a difference in the input values, drive the 7th arm (6) and disconnect from Luhe < WJ, and the input value from the second potentiometer (16) becomes the first The direction in which the toe arm (6) should be driven depends on whether the potentiometer I is greater or less than the input value.
Furthermore, the 7th arm with the same meat input value (
6) Stop Fp (judge and operate both valves Fp! (
19u).

(19d) so as to output signals to each of them.

In other words, as the dial opening is operated, °
Based on the information from both potentiometers r141 and 116, the lift arm (6) is driven by a stroke proportional to the operating amount of the dial (151) in the descending or ascending direction corresponding to the operating direction of the dial port 9. Schilling (13) is configured to operate automatically, and by rotating dial 09, and
7 arm by position flrllal (8)
It is designed for rocking operation.

As shown in FIG. 8, the switch ■ is attached to the stay (13), and the switch operating cam Qυ is attached to the support shaft (13).
Normal situation where the lift arm (6) is below the set lift limit (L1) which should be attached to rotate integrally with the i-control machine and operated by the i-control machine purchase port η, and the lift arm (6) is higher than the set lift limit (L1). A first abnormal situation in which the lift arm (6) is raised to the set stop position (L1), and a second abnormal situation in which the lift arm (6) is raised to a higher level than the set stop position (X4). is configured to be detected by the switch (3) based on the rotational position of the support shaft (7).

That is, the lift arm (6) reaches the set lift limit (L).
1) Below, the first part of the cam (company) as shown in Figure 4
The circumferential cam part (21a) faces the switch holder, and the switch (2) is in the first state shown in FIG. 1, where the first terminal (20a) is on and the second terminal (20b) is off. and,
When the first abnormal situation occurs, the second circumferential cam portion C21b) of the cam plate presses the switch
Furthermore, in order for the switch 1 sword to be in the second state where M child (20a) and (2Qb) are both turned off,
! When the situation occurs, @8 circumferential cam portion of cam 211 (21c
) further suppresses the switch, and the first terminal (20a
) is cut and 2nd #A child (20b) enters @3 down ■
The switch f2G is set to . As shown in FIG. 1, an AND circuit (1) is connected between the control mechanism (171) and the ascending pulp operating circuit (19u), and an AND circuit (2) is connected between the control mechanism (171) and the descending pulp operating circuit (19d). of the circuit, the first terminal (20a) is connected to the +1'UE ant ° circuit (■) via the inverter (■), and
The second terminals (20b) are connected to the OR circuits 123+ through inverters, respectively, and the cylinder tlZ is controlled by the control mechanism t171 based on the detection result of the switch.
It also constitutes an automatic operation mechanism that enables the operation of the cylinder 112) and operates the cylinder 112) with priority over the signal from the control mechanism f171. In other words, if there is a switch (J) in the detection state of the normal situation, the link circuit (20) of the AND circuit (■) and the detection switch (R) is turned on, and the link circuit (20) of the OR circuit and the detection switch (2) is turned off. As a result, the pair of pulp operation circuits (19u) and (19d) are respectively controlled by the control mechanism (19u) and (19d).
This makes it possible to operate based on the signal from η.

Then, when the switch field is in the detection state of the first abnormal situation in MU, the pair of linkage circuits ■ and @ are both turned off, so that the descending side pulp operation circuit operates based on the signal from the control mechanism α. (19d) to operate, but
The rising side pulp operating circuit (10u) is operated to the stopped state regardless of the rising operation signal from the control system (171).And, when the switch (2) is in the detection state of the second abnormal state, the above-mentioned Since the linkage circuit FjlI (20) is off and the linkage circuit is on, the descending side pulp operating circuit (19d) is operated to the descending operating state regardless of the ascending operation signal or stop operating signal from the control mechanism Oη. As shown in Fig. 2, because the piston (12a) of the sill opening and the piston rond (12b) are of the abutting type, the cultivating device (4) for lifting and re-laying is difficult.
Even if the +77) arm jumps up due to running vibration, the
6) Mission gauge stopper 1 that determines the ascent limit
In (8a), the above-mentioned stop position (L, ) is set to a position where the operating arm (111) does not collide with the operating arm (111), and even if the first potentiometer t141 malfunctions or is misaligned, the two lifts Even if the rising speed of the arm (6) is adjusted quickly and the arm (6) is driven upward, or if the arm (6) rises too far from the target stop position when it is stopped, the arm (6) may be operated in a raised position or the arm (6) may be operated automatically. The mechanism is stopped at the set stop position (L), so that the pressure oil supplied to the side of the cylinder [21] returns to the tank through the neutral position of the control valve am, and the tilling device (4) is raised. The operating arm σB and part of the stopper (8a
) to avoid collisions.

[Another example]

The tillage device (4) can be changed to a rice transplanter, a plaque, etc.
These are called working devices (4).

@Kigui〒le 0! il may be replaced with a swing lever, and these are collectively referred to as operating tools (151).

In place of the switch (2), a pair of switches for detecting the first and second abnormal situations separately may be employed, and these are collectively referred to as "sensor (2)".

[Brief explanation of drawings]

The drawings show an embodiment of the lift arm operation structure for an agricultural tractor according to the VC of the present invention, in which Fig. 1 is an electric circuit diagram, Fig. 2 is a cross-sectional view of the moving part of the lift arm W1, and Fig. 3 is a part of the potentiometer installation part. FIG. 4 is a partially cutaway side view of the detection switch installation portion, and FIG. 5 is a partially cutaway side view of the riding power cultivator. (4)...Working equipment, (6)...7
Tor arm, uz...Hydraulic actuator, +1
41...1st potentiometer, (19...
...Operating tool, 06)...Second potentiometer -
ri, surface...control mechanism, ■...q:yf
-1QS-... Automatic operation mechanism, (L1)...
...Setting ascent limit, I' L1) ...Setting stop position. Attorney Attorney ± 4 Hi Mura Osamu 1:0

Claims (1)

[Claims] A lift arm (6) connects the work device (4) so that it can be raised and lowered.
), a first potentiometer (14) detects the mounting height of the lift arm (14) to the aircraft, and a second potentiometer (14) detects the amount of operation of the operating tool (15) with respect to the lift arm (6).
16), and both potentiometers (14), (1
6) A lift arm operating structure for an agricultural tractor including a control mechanism (17) that automatically operates a lift arm drive hydraulic actuator (12) based on information from
A first situation in which the lift arm (6) is raised to a set stop position (L_2) higher than the set lifting limit (L_1) to be operated by the control mechanism (17), and the set stop position (L_1) a sensor (
20), and when the sensor (20) is in the detection state of the first situation, it automatically stops the hydraulic actuator (12) in priority over the control mechanism (17), and The sensor (
20) is provided with a mechanism (25) that automatically operates the hydraulic actuator (12) to the lowering side of the lift arm with priority over the control mechanism (17).